The present invention relates to an assembly for sealing valve stem, and more particularly to an assembly which includes a valve stem seal having a generally cylindrical elastic member with a sealing portion which slidably rests on the valve stem and with a connection portion which is mounted on the valve stem bushing, the valve stem seal additionally having a preferably metal stiffening ring which is vulcanized to the elastic member. Such a valve stem seal is typically used in conjunction with at least one spring which concentrically surrounds the valve stem, and a valve spring retainer which is connected with the valve stem.
U.S. Pat. No. 4,531,483 discloses a valve steam seal having a generally cylindrical elastic member with a sealing portion which slidably rests on the valve stem and with a connection portion which can be mounted on the valve steam bushing, the valve stem, seal additionally having a stiffening ring. With the aid of an assembly punch, the attachment portion of the valve stem seal is pressed onto the tubular valve stem bushing. To maintain a secure seat and proper operation, the valve stem bushing must be machined with precision; additionally, the valve stem seal requires an axial abutment to provide a neat seat at the valve stem bushing or at the cylinder head. Only after the valve stem seal has been properly installed can the remaining parts, such as a valve spring retainer, valve spring, and valve collet, be assembled.
In automatic fabrication, a separate manipulating machine is required for each part; additionally all individual parts must be stored separately.